Abstract:This dissertation investigates regional transportation planning in California from 1967 through the contemporary era, identifying advocates for regional equity as important actors for achieving desired planning outcomes including climate change mitigation. It begins with the creation of the California Department of Transportation (Caltrans). Replacing its predecessor organization in 1973, the creation of Caltrans was thought to signal the beginning of multimodalism in state transportation policy. Opposition from the public and the legislature to this new direction led to the establishment of regional transportation planning organizations that actually located authority at the local (city and county) level. California’s transportation policy goals embodied in the contemporary Senate Bill (SB) 375 are similar to those of the 1970s – reducing vehicle-miles traveled through the promotion of compact urban forms – but the institutional arrangements established in the 1970s make progress difficult to achieve. Regional equity advocates are emerging as an important constituency in this fraught planning landscape. Buoyed by foundation funding and federal legislation enacted beginning with Title VI of 1964’s Civil Rights Act, these advocates are seeking to ensure that agencies meet planning goals where the law is insufficiently prescriptive. A key method by which advocates access the planning process is through the “equity analysis” of regional transportation plans. A critical review of equity analysis practice reveals standard methods that are not responsive to public input and do not take advantage of recent developments in activity-based travel demand modeling. Improved methods are proposed that are developed in collaboration with equity advocates. Although these improvements will not ensure equitable outcomes, they represent an improvement over existing analysis techniques, more accurately reflect the concerns of advocates, and could be deployed nationwide.